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What is the difference between vicodine and Tylnol with codeine? Is it ok to mix promethazine-codeine and xanax? . It has dextromethophan (DM) which is in the same class of drugs as codeine, so yes it has ingredient that's very similar to.

The difference is in the cough medicine present in them. Promethazine VC has only phenylephrine, a decongestant. Promethazine DM as dextromethorphan, an anti-tussive that is rather effective and over the counter (on its own- It is the ingredient found in robitussin). Promethazine with Codeine is much stronger and contains codeine, a prescription drug. It tends to be the most effective. As long as you dont mix them (dosing with promethazine can be tricky, so you dont want to take multiple drugs containing it), you should be safe to take any one of them, given that you arent allergic to any of the ingredients, follow correct doses, etc.